Front Cover -- Plant Biochemistry -- Copyright Page -- Contents -- Chapter 1. A leaf cell consists of several metabolic compartments -- 1.1 The cell wall gives the plant cell mechanical stability -- 1.2 Vacuoles have multiple functions -- 1.3 Plastids have evolved from cyanobacteria -- 1.4 Mitochondria also result from endosymbionts -- 1.5 Peroxisomes are the site of reactions in which toxic intermediates are formed -- 1.6 The endoplasmic reticulum and Golgi apparatus form a network for the distribution of biosynthesis products -- 1.7 Functionally intact cell organelles can be isolated from plant cells -- 1.8 Various transport processes facilitate the exchange of metabolites between different compartments -- 1.9 Translocators catalyze the specific transport of substrates and products of metabolism -- 1.10 Ion channels have a very high transport capacity -- 1.11 Porins consist of β-sheet structures -- Further reading -- Chapter 2. The use of energy from sunlight by photosynthesis is the basis of life on earth -- 2.1 How did photosynthesis start? -- 2.2 Pigments capture energy from sunlight -- 2.3 Light absorption excites the chlorophyll molecule -- 2.4 An antenna is required to capture light -- Further reading -- Chapter 3. Photosynthesis is an electron transport process -- 3.1 The photosynthetic machinery is constructed from modules -- 3.2 A reductant and an oxidant are formed during photosynthesis -- 3.3 The basic structure of a photosynthetic reaction center has been resolved by X-ray structure analysis -- 3.4 How does a reaction center function? -- 3.5 Two photosynthetic reaction centers are arranged in tandem in photosynthesis of algae and plants -- 3.6 Water is split by photosystem II -- 3.7 The cytochrome-b6/f complex mediates electron transport between photosystem II and photosystem I -- 3.8 Photosystem I reduces NADP.

3.9 In the absence of other acceptors electrons can be transferred from photosystem I to oxygen -- 3.10 Regulatory processes control the distribution of the captured photons between the two photosystems -- Further reading -- Chapter 4. ATP is generated by photosynthesis -- 4.1 A proton gradient serves as an energy-rich intermediate state during ATP synthesis -- 4.2 The electron chemical proton gradient can be dissipated by uncouplers to heat -- 4.3 H+-ATP synthases from bacteria, chloroplasts, and mitochondria have a common basic structure -- 4.4 The synthesis of ATP is effected by a conformation change of the protein -- Further reading -- Chapter 5. Mitochondria are the power station of the cell -- 5.1 Biological oxidation is preceded by a degradation of substrates to form bound hydrogen and CO2 -- 5.2 Mitochondria are the sites of cell respiration -- 5.3 Degradation of substrates for biological oxidation takes place in the matrix compartment -- 5.4 How much energy can be gained by the oxidation of NADH? -- 5.5 The mitochondrial respiratory chain shares common features with the photosynthetic electron transport chain -- 5.6 Electron transport of the respiratory chain is coupled to the synthesis of ATP via proton transport -- 5.7 Plant mitochondria have special metabolic functions -- 5.8 Compartmentation of mitochondrial metabolism requires specific membrane translocators -- Further reading -- Chapter 6. The Calvin cycle catalyzes photosynthetic CO2 assimilation -- 6.1 CO2 assimilation proceeds via the dark reaction of photosynthesis -- 6.2 Ribulose bisphosphate carboxylase catalyzes the fixation of CO2 -- 6.3 The reduction of 3-phosphoglycerate yields triose phosphate -- 6.4 Ribulose bisphosphate is regenerated from triose phosphate -- 6.5 Besides the reductive pentose phosphate pathway there is also an oxidative pentose phosphate pathway.

6.6 Reductive and oxidative pentose phosphate pathways are regulated -- Further reading -- Chapter 7. In the photorespiratory pathway phosphoglycolate formed by the oxygenase activity of RubisCo is recycled -- 7.1 Ribulose 1,5-bisphosphate is recovered by recycling 2-phosphoglycolate -- 7.2 The NH4+ released in the photorespiratory pathway is refixed in the chloroplasts -- 7.3 For the reduction of hydroxypyruvate, peroxisomes have to be provided with external reducing equivalents -- 7.4 The peroxisomal matrix is a special compartment for the disposal of toxic products -- 7.5 How high are the costs of the ribulose bisphosphate oxygenase reaction for the plant? -- 7.6 There is no net CO2 fixation at the compensation point -- 7.7 The photorespiratory pathway, although energy-consuming, may also have a useful function for the plant -- Further reading -- Chapter 8. Photosynthesis implies the consumption of water -- 8.1 The uptake of CO2 into the leaf is accompanied by an escape of water vapor -- 8.2 Stomata regulate the gas exchange of a leaf -- 8.3 The diffusive flux of CO2 into a plant cell -- 8.4 C4 plants perform CO2 assimilation with less water consumption than C3 plants -- 8.5 Crassulacean acid metabolism makes it possible for plants to survive even during a very severe water shortage -- Further reading -- Chapter 9. Polysaccharides are storage and transport forms of carbohydrates produced by photosynthesis -- 9.1 Large quantities of carbohydrate can be stored as starch in the cell -- 9.2 Sucrose synthesis takes place in the cytosol -- 9.3 The utilization of the photosynthesis product triose phosphate is strictly regulated -- 9.4 In some plants assimilates from the leaves are exported as sugar alcohols or oligosaccharides of the raffinose family -- 9.5 Fructans are deposited as storage substances in the vacuole.

9.6 Cellulose is synthesized by enzymes located in the plasma membrane -- Further reading -- Chapter 10. Nitrate assimilation is essential for the synthesis of organic matter -- 10.1 The reduction of nitrate to NH3 proceeds in two partial reactions -- 10.2 Nitrate assimilation also takes place in the roots -- 10.3 Nitrate assimilation is strictly controlled -- 10.4 The end product of nitrate assimilation is a whole spectrum of amino acids -- 10.5 Glutamate is precursor for synthesis of chlorophylls and cytochromes -- Further reading -- Chapter 11. Nitrogen fixation enables the nitrogen in the air to be used for plant growth -- 11.1 Legumes form a symbiosis with nodule-forming bacteria -- 11.2 N2 fixation can proceed only at very low oxygen concentrations -- 11.3 The energy costs for utilizing N2 as a nitrogen source are much higher than for the utilization of NO3- -- 11.4 Plants improve their nutrition by symbiosis with fungi -- 11.5 Root nodule symbioses may have evolved from a preexisting pathway for the formation of arbuscular mycorrhiza -- Further reading -- Chapter 12. Sulfate assimilation enables the synthesis of sulfur-containing substances -- 12.1 Sulfate assimilation proceeds primarily by photosynthesis -- 12.2 Glutathione serves the cell as an antioxidant and is an agent for the detoxification of pollutants -- 12.3 Methionine is synthesized from cysteine -- 12.4 Excessive concentrations of sulfur dioxide in air are toxic for plants -- Further reading -- Chapter 13. Phloem transport distributes photoassimilates to the various sites of consumption and storage -- 13.1 There are two modes of phloem loading -- 13.2 Phloem transport proceeds by mass flow -- 13.3 Sink tissues are supplied by phloem unloading -- Further reading -- Chapter 14. Products of nitrate assimilation are deposited in plants as storage proteins.

14.1 Globulins are the most abundant storage proteins -- 14.2 Prolamins are formed as storage proteins in grasses -- 14.3 2S-Proteins are present in seeds of dicot plants -- 14.4 Special proteins protect seeds from being eaten by animals -- 14.5 Synthesis of the storage proteins occurs at the rough endoplasmic reticulum -- 14.6 Proteinases mobilize the amino acids deposited in storage proteins -- Further reading -- Chapter 15. Glycerolipids are membrane constituents and function as carbon stores -- 15.1 Polar glycerolipids are important membrane constituents -- 15.2 Triacylglycerols are storage substances -- 15.3 The de novo synthesis of fatty acids takes place in the plastids -- 15.4 Glycerol 3-phosphate is a precursor for the synthesis of glycerolipids -- 15.5 Triacylglycerols are formed in the membranes of the endoplasmic reticulum -- 15.6 During seed germination, storage lipids are mobilized for the production of carbohydrates in the glyoxysomes -- 15.7 Lipoxygenase is involved in the synthesis of oxylipins, which are acting as defense and signal substances -- Further reading -- Chapter 16. Secondary metabolites fulfill specific ecological functions in plants -- 16.1 Secondary metabolites often protect plants from pathogenic microorganisms and herbivores -- 16.2 Alkaloids comprise a variety of heterocyclic secondary metabolites -- 16.3 Some plants emit prussic acid when wounded by animals -- 16.4 Some wounded plants emit volatile mustard oils -- 16.5 Plants protect themselves by tricking herbivores with false amino acids -- Further reading -- Chapter 17. A large diversity of isoprenoids has multiple functions in plant metabolism -- 17.1 Higher plants have two different synthesis pathways for isoprenoids -- 17.2 Prenyl transferases catalyze the association of isoprene units -- 17.3 Some plants emit isoprenes into the air.

17.4 Many aromatic substances are derived from geranyl pyrophosphate.